Tubular endoprosthesis for anatomical conduits

ABSTRACT

Tubular endoprosthesis for anatomical conduits is provided with a tubular body having an external surface which includes a plurality of protuberances. Preferably, the protuberances are distributed on the totality of the external surface, and are composed of nipples having a round apex, spaced from each other and radially oriented with respect to the tubular body.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention concerns a tubular endoprosthesis for anatomicalconduits or channels. Specifically, particular nonlimiting embodimentsof this endoprosthesis are intended to permit the clearance of hardenedconduits such as the trachea or bronchus, or to serve as a support forsuch anatomical conduits when they prove to be weak. Also described isan instrument to put this endoprosthesis in place.

2. Description of Background and Relevant Information

A hollow tube is disclosed in French Patent Document No. 1,130,165 forthe treatment of hardening of the esophagus. The device constitutes aflexible tube with a ribbed external surface intended to be installed ina tumoral contraction to permit the passage of food.

This hollow tube has the drawback of not offering any guarantee that itwill stay in place, because it can easily turn on itself, which canprovoke irritation. Such irritation generates rejection spasms leadingto axial shift of the tube, along with the serious consequences to whichthis shift can lead.

SUMMARY OF THE INVENTION

One of the objects of the present invention is to effectively remedythis serious insufficiency of known endoprostheses.

According to the invention, this objective is obtained by means of anendoprosthesis with a tubular body whose external surface is providedwith numerous protuberances or asperities, preferably distributed overthe entire surface, or a portion thereof. These protuberances consistsof nipples with rounded tops, which are spaced from each other in thelongitudinal and peripheral directions on the tubular body, and arepreferably radially-oriented.

Another advantage of the endoprosthesis according to the invention isthat it can be put easily in place and installs itself in a natural,extremely resistant fashion. In its implantation position, theprosthesis cannot, in effect, turn or slide axially when it is installedin the stenosis. In addition, this prosthesis may be made of a plasticmaterial, such as an elastomer silicone, which is well tolerated by theorganism whether healthy or ill, in whom it does not produce rejectionspasms or trauma.

In another embodiment of the tubular endoprosthesis according to theinvention, the nipples are arranged in lines with spaces in between themand are oriented along the rulings of the tubular body of theendoprosthesis.

The nipples can also be alternatingly distributed on the externalsurface of the tubular body.

In another embodiment of the tubular endoprosthesis according to theinvention, at least one of its ends has an internal slanted wall.Optionally, both or all of its ends may have an internal slanted wall.

The goals, characteristics, and advantages above, and others, will bemore apparent from the following description and the attached Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the tubular endoprosthesis according tothe invention.

FIG. 2 is a lengthwise cross-section of the tubular endoprosthesis shownin FIG. 1.

FIG. 3 is a transverse cross-section of the tubular endoprosthesis shownin FIG. 2.

FIG. 4 is an enlarged view, in detail, of a lengthwise cross-section ofone of the ends of the endoprosthesis.

FIG. 5 is a front view of an embodiment of utilizing the endoprosthesisaccording to the invention, to permit tracheal bronchus clearance.

FIG. 6 is a view of the instruments permitting the placement of anendoprosthesis like the one illustrated in FIGS. 1-4.

FIGS. 7-11 show the operation of the placement instrument shown in FIG.6 and the installation method for the tubular endoprosthesis accordingto the invention.

FIG. 12 is a front view of another embodiment of a tracheal bronchusendoprosthesis according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

We refer to the following embodiments to describe the non-limitingconstruction of this endoprosthesis, as well as the use of instrumentspermitting its installation.

The tubular endoprosthesis according to the invention can, as a functionof the shape of the anatomical conduit or channel inside which it isintended to be installed, affect a variety of shapes. Particularembodiments have a simple rectilinear or essentially rectilinear shape(for example, when it is a tracheal endoprosthesis or bronchusendoprosthesis) as shown in FIG. 1, or a curved shape. Anotherembodiment has a more complex shape with a principle tube extending intotwo divergent tubular branches (when it is a trachea bronchusendoprosthesis) as shown in FIG. 5. More precisely, this endoprosthesiscan have any shape and any diameter adapted to the shape and thediameter of the conduits, channels or vessels inside which it is to beplaced. The endoprosthesis can be made in any supple, semi-rigid, orrigid material, and may be reinforced by an internal reinforcementcapable of being well-tolerated by the organism. Preferred embodimentscan be advantageously made in a material with an elastic deformationcapacity which in a particularly preferred embodiments is an elastomersilicon.

According to one embodiment of the invention, the endoprosthesis has atubular body 1 with an external surface 2, which is intended to comeinto contact with the internal wall of an anatomical conduit. Externalsurface 2 is provided with numerous protuberances or asperities 3, whichmay be distributed evenly over the entire external surface 2 orpositions thereof.

These protuberances or asperities 3 can have very different shapes,without edges that could injure the anatomical walls with which they aresupposed to come into contact. In a preferred embodiment theproterberances or asperities 3 consist of nipples with rounded tops,arranged in lines oriented according to the rulings of theendoprosthesis; these lines of nipples can be angularly spaced, as shownparticularly in FIG. 1. These nipples 3 are radially-oriented inrelation to the tubular body 1, and they are spaced from each other inthe lengthwise direction as well as the peripheral direction. They canbe advantageously distributed alternately on the lateral surface of thetubular body 1. The nipples can have a circular or any other shapedsection. Also, these nipples or nibs 3 are ineffaceable, that is, theyare sufficiently rigid so that they don't compress, bend, or retractunder the conditions of use.

At least one, and preferably both ends, of the endoprosthesis areprovided with an internal sloping edge 4 (FIG. 4), so that the endsconsist of thin, tapered lips. This feature provides that when theendoprosthesis is in place, it forms no retention asperity favoring theformation of diverse accumulations as a function of the nature of theconduits, channels or vessels, at the entry or exit of the prosthesis.

The alternative embodiment of the prosthesis illustrated in FIG. 5differs from the preceding only by its slightly more complex shapeadapted to the conformation of the conduits in which it is to beinstalled. According to this variation of construction, the prosthesisincludes a principal tubular body 1' extended by two divergent tubularbranches 1"; the external surfaces 2', 2" of the main body and of thebranches are provided with nipples 3, as previously described. Such aprosthesis is intended to be placed at the branching point of ananatomical conduit. According to a very interesting application, such aprosthesis is intended to constitute a tracheobronchus endoprosthesis,allowing the conduit to remain open despite an obstruction S affectingboth the internal part of the trachea T and the initial portion of thetwo bronchi B to be by-passed.

FIG. 12 shows another embodiment of a prosthesis according to theinvention such as a tracheobronchus endoprosthesis, also intended to beplaced at the branching point of an anatomical conduit, such as in thecase of an obstruction S to be by-passed affecting only the base of themajor conduit (trachea T, for example) and only one of the branches (oneof the bronchi B', for example). In this case, the prosthesis has acurved shape and includes a major part 10 extended by a second part ofsmaller diameter 10'. In addition, it has an opening 9 laterally placedat the juncture point of the major part 10 and secondary part 10', theopening 9 is intended to be placed at the entry of a second healthybranch of an anatomical conduit (the other bronchus B", for example), inorder to permit a passage between the principal conduit T and a healthybranch B".

The lateral opening 9 can also allow and favor the installation of asecond independent tubular branch similar to the secondary part 10', inorder to create an endoprosthesis like the one shown in FIG. 5.

We have shown in FIG. 6 an installation or introduction instrument forendoprosthesis consisting of a rectilinear or essentially rectilineartube such as those which are intended to be installed in the trachea orin the weak, hardened or tumor-compressed bronchi, in order to serve astheir support or to permit them to be cleared.

This instrument includes a classic bronchoscope 6 on the elongatedcylindrical body or guidance rod 6a, on which is mounted, with a slidingability in relation to said rod, a tubular pusher 7 whose length L' isless than the length L of the guidance rod 6a. The difference in lengthbetween the rod 6a of the bronchoscope and the pusher 7 corresponds atleast to the length L" of the endoprosthesis 8 intended to be introducedand positioned with the help of the instrument; this difference inlength (L--L') being, however, preferably greater than the length L' ofthe endoprosthesis.

FIGS. 7-11 show the installation procedure of a simple endoprosthesis 8in an anatomical conduit B (for example, trachea or bronchus) obstructedby a compressive tumor S.

The endoprosthesis 8 is first placed around the end of the rod 6a of thebronchoscope 6, in front of the pusher 7 (FIG. 7), the tapered end ofthe rod emerging at the front of the endoprosthesis, in order tofacilitate its progress in the anatomical conduit.

The rod furnished with endoprosthesis 8 is then introduced and driveninto the anatomical conduit B (FIG. 8) until said endoprosthesis reachesthe desired position (FIG. 9), that is, the place where the hardening orcompressive tumor is located.

The rod 6a of the bronchoscope is then withdrawn while maintaining thepusher 7 in place, which prevents any backwards movement of theendoprosthesis during this withdrawal (FIG. 10). Finally, the pusher iswithdrawn, the endoprosthesis then being installed and solidly fixed inits lodging because of the nipples provided on its external surface, onwhich the surrounding anatomical wall exerts pressure preventing anyshift or movement of the endoprosthesis.

I claim:
 1. Tubular endoprosthesis for anatomical conduits, comprising:abiocompatible tubular body composed of a semi-rigid or rigid materialhaving an external surface and two open ends forming a passagetherethrough, said body adapted to contact an internal wall of theanatomical conduit; and means forming a plurality of discreteprotuberances distributed on said external surface for maintaining saidtubular body within said anatomical conduit against return or axialdisplacement without injuring the internal wall of the anatomicalconduit; and said means forming a plurality of protuberances comprisingineffaceable nipples having rounded tops, with said nipples being spacedalong the length and periphery of said external surface of said tubularbody.
 2. The tubular endoprosthesis according to claim 1, wherein saidnipples are radially oriented with respect to said tubular body.
 3. Thetubular endoprosthesis according to claim 1, wherein said nipples havingrounded tops are distributed over substantially the entire externalsurface of said tubular body.
 4. The tubular endoprosthesis according toclaim 1, wherein said nipples are arranged in lines which are spacedfrom each other along said length of the external surface.
 5. Thetubular endoprosthesis according to claim 4, wherein said lines arepositioned along rulings of said tubular body.
 6. The tubularendoprosthesis according to claim 5, wherein said nipples arealternately distributed along said tubular body.
 7. The tubularendoprosthesis according to claim 1, wherein said semi-rigid or rigidmaterial comprises a material having elastic deformation ability.
 8. Thetubular endoprosthesis according to claim 7, wherein said material is anelastomeric silicone.
 9. The tubular endoprosthesis according to claim1, wherein said tubular body includes a lateral opening adapted tomaintain a passage between an anatomical conduit in which the tubularendoprosthesis is positioned and a branch thereof.
 10. Tubularendoprosthesis for anatomical conduits, comprising:a biocompatibletubular body having an external surface, wherein said tubular bodyincludes two open ends, and at least one of said two ends has aninternal slanted wall; and means forming a plurality of protuberancesdistributed on said external surface for maintaining said tubular bodyin an anatomical conduit without injuring anatomical walls of theanatomical conduit; and said means forming a plurality of protuberancescomprising nipples having rounded tops, with said nipples being spacedalong the length and periphery of said external surface of said tubularbody.
 11. The tubular endoprosthesis according to claim 10, wherein eachof said two ends has an internal slanted wall.